How to Count the Number of Times a Character Appears in a String Using JavaScript?

To count the number of times a character appears in a string using JavaScript, you can use the split() method to convert the string into an array of characters, and then use the filter() method to create a new array with all elements that match the character you’re searching for. Finally, you can use the length property to determine the number of elements in that new array. Here’s an example:

function countCharacter(str, char) {
  return str.split("").filter(c => c === char).length;
}

const sentence = "Count the number of times the character 'e' appears in this sentence.";
const count = countCharacter(sentence, "e");
console.log(`The character 'e' appears ${count} times in the sentence.`);

In the example above, the countCharacter function takes a string and a character as arguments. The split() method is used to convert the string sentence into an array of characters using an empty string as a separator. The filter() method is then used to create a new array with all elements that match the character "e", and the length property is used to determine the number of elements in that array, which represents the number of times the character appears in the original string. The result is logged to the console.